This invention relates to non-combustible nicotine dispensing devices designed to reduce or eliminate the disadvantages associated with conventional smoking habits.
Nicotine is a liquid alkaloid having the empirical formula C.sub.10 H.sub.14 N.sub.2. When nicotine is obtained from tobacco, as by chewing, sniffing or smoking the substance, the amount of nicotine absorbed into the body generally does not build up to a harmful dose, but produces certain pleasurable effects, frequently leading to habitual use.
One of the most popular versions of nicotine use involves the smoking of cigarettes. When the tobacco in a conventional cigarette is ignited, the combustion of the processed tobacco leaves within the cigarette causes the release of vaporous nicotine, which is drawn through the cigarette and into the user's mouth and lungs when the user sucks or inhales air through the cigarette.
The relative mildness of a cigarette, as compared to a pipe or cigar, permits a user to draw the smoke from the burning cigarette directly into the lungs. Nicotine in the cigarette smoke is rapidly assimilated into the bloodstream of the user from the lungs, so that cigarette smoking provides a method by which a user may very quickly feel the effects of the nicotine.
Although nicotine may be readily introduced into the body through cigarette smoking, the combustion of the tobacco, with the consequent elevated temperatures required in this process, unfortunately results in a number of undesirable consequences associated with smoking combustible cigarettes. Of primary concern are the serious health hazards thought by many to result from smoking combustible cigarettes. Although the nicotine content of a cigarette is not believed to cause serious adverse long-term health effects on the human body, other components are present in tobacco smoke which are thought by many to be harmful. Some of these other constituents appear to be carcinogenic.
Furthermore, the smoking of combustible cigarettes may pose a significant fire hazard. Many fires which have occurred both within buildings or in natural environments have been attributed to carelessly discarded burning cigarettes. In addition, substantial economic losses may be attributed to smoking, including, for example, significant damages to business and personal property resulting from burns in clothing, carpeting, furniture, etc. caused by stray ashes from cigarettes. Cigarette smoking has also become increasingly objectionable because of the discomfort it may cause to non-smokers who are exposed to the smoke and odor produced by practitioners of the smoking habit.
Because of these undesirable side effects of combustible cigarette smoking, attempts have been made from time to time to provide an acceptable substitute for combustible cigarette smoking which eliminates or ameliorates some or all of the adverse consequences mentioned above. Tobacco concentrates, for example, have been processed into a tablet form which may be sucked or chewed, the nicotine being absorbed into the user's body through the lining of the mouth and digestive system. Such a tablet, of course, does not provide the user with the feel of a cigarette held between the lips.
Furthermore, a tablet-type smoking substitute cannot provide the user with an opportunity to draw air and vapors into the mouth nor inhale the air and vapors into the lungs, these actions being a part of the conventional smoking habit. These actions or activities constitute an important aspect of the psychological and physiological affinities which a smoker acquires for the habit. Without an effective substitute for such smoking activities, a smoking substitute is less likely to satisfy the smoker and may thus result in the smoker's return to combustible cigarette smoking.
An important step forward in the development of a smoking substitute is described in U.S. Pat. No. 4,284,089 to Ray, assigned to the assignee o the present invention. In this patent a smokeless device for dispensing nicotine is described which may take the appearance of a conventional smoking item such as a cigarette. Moreover, the device disclosed in that patent enables nicotine to be dispensed in response to users action that closely simulates conventional smoking activity.
In an illustrated embodiment, the Ray patent discloses a device having the general configuration of cigarette. However, the interior of the device defines a gas flow passageway with a flow restriction. The flow restriction is defined by an absorbent material carrying a nicotine solution on the material. In response to the fluid velocity developed at the restriction, nicotine is vaporized from the absorbent material and inhaled by the user. As a result, the user attains a nicotine induced sensation quite similar to that obtained by smoking conventional cigarettes.
While it may be safely posited that the Ray patent represents a pioneering advance in the art, the inventor of the present invention has appreciated that it would be desirable to optimize the performance of a device of the type disclosed in the Ray patent. Particularly, the present inventor has appreciated that it would be highly desirable to increase the amount of nicotine that is vaporized in response to a given puff on such a device.
It is also very important in a device of this kind to efficiently vaporize the nicotine. Liquid nicotine has an extremely bitter, almost caustic taste. Thus, it is important to dispense the nicotine in fashion which encourages vaporization while preventing inadvertent suction of unvaporized droplets, even those of very small size, commonly called an aerosol.
The present inventor has also appreciated that it is important that the nicotine be dispensed in relatively uniform dosages over the life of the product. Unless the user can depend on a steady dosage of nicotine, the use of the dispensing device may be considered less enjoyable than smoking tobacco. Furthermore, it is important for the user to easily determine when the product is depleted which is the case when nicotine delivery is regular prior to exhaustion.
Finally the present inventor appreciated that the above described objectives are most advantageously achieved with a device having a "draw" similar to that of a conventional smoking device, such as a cigarette. It is believed that users may rapidly become dissatisfied with a smoking substitute that requires too little or, more particularly, too much inhalation effort for the sensation achieved. Similarly if the device dispenses too high a nicotine dosage with each puff, the user may receive more nicotine than desired and may be forced to change smoking habits. Either of these alternatives is undesirable in that the user will be less willing to substitute the smokeless substitute if the "familiar feeling" is compromised or if the substitute is somehow less pleasurable.